1. Field of the Invention
This invention pertains to a centrifugal pump which in its conventional form comprises an impeller fitted with vanes and rotating in a closed casing. Fluid enters the casing at the center of the impeller where, due to the rotation of the impeller, the pressure of the fluid is increased and the fluid is delivered to the periphery at a high velocity. Rotation of the impeller is activated by an external electric motor shaft penetrating into the closed casing (volute) onto which the impeller is attached.
2. Description of the Related Art
U.S. Pat. No. 3,134,332, Nielson 1964, describes a conventional centrifugal pump with an electric motor driving the impeller. U.S. Pat. No. 4,773,822 Jensen et al 1988, describes the separation between the rotating impeller inlet and the volute supply inlet allowing a certain percentage of the pumped fluid to reenter the impeller suction inlet. U.S. Pat. No. 4,773,823, Pease 1988, describes the complexity of included parts in a conventional motor driven pump.